Buyer Says They didnt receive delivery – But USPS tracking says it was delivered. OPTIONS?

Hey all,

I’ve been selling exclusively through Amazon for over a year now. I’m here at Reddit asking for community advice because Amazon’s customer service is hot garbage. I send my orders via USPS and UPS directly from merchant to customer. 99% of my shipments go through USPS Ground Advantage, each with tracking numbers. I’ve had a few orders where the customer says they didnt receive the order, but USPS tracking shows it was delivered to their mailbox. What’s the options?

– USPS Claim? I’ve had 50:50 success with them. If their currier marks the package as Delivered, I’m sh&t out of luck. USPS hits me with, “Denied – Records indicate delivery of article”